1. Field of the Invention
The present invention relates to a power-saving power supply apparatus, and in particular to a power-saving power supply apparatus with battery module.
2. Description of Prior Art
Since the resources in earth are decreasing gradually, nations all over the world attempt to develop alternative energy resources or renewable energy resources to solve the possible problem that the lack of resources may cause economical crisis or affect the industries seriously. In addition to develop new energy sources, saving power is also important to do. Thus, developing new energy sources and saving power can be implemented at the same time without coming into conflict, whereby the power sources in earth can be used for a longer period of time. Thus, many people start to pay attention to the solutions of saving power in various sites. For example, people intend to save water, electricity and gasoline in their daily life, offices or business sites. In order to promote the power-saving effect, the Government has issued some policies to reward the execution of saving power in a house, office or business site. For example, in order to encourage the user to consume power more frugally, the Power Company signs a contract with the user in which a contract capacity is prescribed as the basis of counting the power bill. If the power consumed by the user exceeds the contract capacity, the user has to pay the power bill with different multiples, whereby the unnecessary consumption of electricity can be reduced. Therefore, we have to save power at anytime and anyplace.
It is necessary to use a power supply to maintain the operation of an electric appliance. Thus, a power supply apparatus is used to supply power to the electric appliance. The input end, usually a plug, of the power supply device is connected to a power socket so as to receive 110V-220V AC power. The output end of the power supply apparatus is to output a power suitable for the operation of the electric appliance. When the electric appliance is not used, however, the plug of the power supply apparatus usually remains connected to the power socket. People often forget to remove the plug from the power socket for two reasons. Removing the plug from the power socket repeatedly is inconvenient for the user. On the other hand, the repeated removal and connection of the plug may cause the plug and power socket to suffer damage. However, when the plug of the power supply apparatus is connected to the power socket, a small amount of power is still consumed even the electric appliance is not in operation. Such a small consumption of electricity may result from the elements within the power supply apparatus (such as rectifier, filter, transistors, coils or the like) and will generate heat inevitably. After the accumulation for a long period of time, such a small consumption of electricity may become significant.
According to prior art, the existing solution is to provide a switch element such as a relay in the input end of AC power, thereby rendering a mechanism for shutting off AC power. However, providing an additional switch element in the input end of AC power has drawbacks including the increase in cost, the reduction in conversion efficiency, and the deterioration of heat dissipation.
Therefore, it is an important issue to provide a power supply apparatus, which can detect whether it is idle or under a low workload and, if necessary, automatically shut off the AC power at the input end, thereby reducing the cost without deteriorating the conversion efficiency and the heat-dissipating effect. Even the electric appliance is not in use while the plug of the power supply apparatus remains connected to the power socket, the user needs not to worry about the waste of electricity.